External modules allow C code to be dynamically loaded (on
architectures that permit) to extend the Lisp environment in
basically the same way that loading Lisp code does.

Status

I propose that the code be left in and advertised as a feature
available for experimentation, but the autoconf feature be off by
default. There is insufficient time and energy for extensive
discussion of this matter for a March 1 release.

External modules (J. Kean Johnston) have been static for a while.
Stable? I don't know. The base64 module works for me. Jerry
James has a project that uses them. But I don't believe they're
getting thorough testing, the sample module never got implemented,
and the eudc and zlib modules are partial implementations AFAICT.

Kean has not responded to an inquiry about status. I know that
Hrvoje at least objected to the external modules on the basis that
they expose the C interfaces to "user" code, restricting developer
flexibility in changing C code.

Open bugs

None.

Other open issues

None.

Discussion

According to Andy: J. Kean Johnson has been out
of contact for a while - but someone else is actively hacking on
them so you should consult xemacs-beta on this. This guy also made
them work under mswindows and cygwin (which was my only objection
to them going in) so I think they should go in. I don't think
their presence compromises stability in any way.